Glucosamine is extracted from the shell of crabs, lobster and shrimps, and also peddled by Cargill in a non-animal, non-shelfish derived product. Glycosaminoglycans and glycoproteins allow cells in tissues to hold together. Glucosamine is an aminomonosaccharide, a constituent of almost all human tissues, including cartilage. It is the principle component of O- and N-linked glycosaminoglycans, that form the matrix of all connective tissues. Chondroitin sulfate is extracted from animal cartilage like shark cartilage.

Glucosamine and chondroitin sulfate are used to treat osteoarthritis. The multi-center, double-blind, placebo- and celecoxib-controlled Glucosamine/chondroitin Arthritis Intervention Trial (GAIT) assessed their potency and safety as a treatment for knee pain from osteoarthritis. Glucosamines and chondroitin sulfates are extracted from sea molluscs (such as Perna canaliculus), from shark skeleton, as well as from cattle.

Glucosamine is a form of amino sugar which is supposed to play a role in cartilage formation and repair. Glucosamine sulphate offers the raw material required by the body to manufacture joint cartilage. Chondroitin sulfate is a major integrant of cartilage, providing structure, holding water and nutrients, and allowing other molecules to move through cartilageľa vital function, as there is no blood supply to cartilage.

Chondroitin sulfate is part of a large protein molecule (proteoglycan) which gives cartilage elasticity. Glucosamine sulfate offers pain relief and improved function in knee OA. Glucosamine and chondroitin sulfates might be used in any joint condition involving the paradigmatical joint structure (2 bones with cartilage covered ends articulating, a fibrous capsule with ligaments connecting the bones, and lubricating fluid abetting the smooth motion of the joint). Glucosamine and chondroitin sulfates are not likely to be helpful with disease involving other types of joints (ie the vertebrae and intervertebral discs).

Glucosamine sulfate 1500 mg daily in divided doses for patient with symptomatic OA may be considered. Chondroitin sulfate may be considered in the treatment of pain from OA and may be given in the amount of 1,200 mg/day or 400 mg tid. Effectuality of a single daily dose of 1,200 mg/day does not seem to differ from that of 400 mg given tid. In the nervous system, Chondroitin Sulfates are attached to a family of proteoglycans which serve to maintain the growth and development of the nervous system as well as the nervous system response to injury. Glucosamine sulphate is produced from the shells of shellfish. People with known shellfish allergies should avoid taking this product.